Several preconditions must be satisfied before a Rb-Sr date can be considered as representing the time of emplacement or formation of a rock. Rb and Sr are relatively mobile alkaline elements and as such are relatively easily moved around by the hot, often carbonated hydrothermal fluids present during metamorphism or magmatism. Conversely, these fluids may metasomatically alter a rock, introducing new Rb and Sr into the rock generally during potassic alteration or calcic albitisation alteration. Rb-Sr can then be used on the altered mineralogy to date the time of this alteration, but not the date at which the rock formed. Thus, assigning age significance to a result requires studying the metasomatic and thermal history of the rock, any metamorphic events, and any evidence of fluid movement. A Rb-Sr date which is at variance with other geochronometers may not be useless, it may be providing data on an event which is not representing the age of formation of the rock. Sampling error is taken into account in all radiometric dating techniques. I have an excellent science background, although I am no Dr. My “theory” is that God used evolution.
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Evidence for Evolution and an Old Earth Evidence for Evolution and an Old Earth, a Catholic Perspective “According to the widely accepted scientific account, the universe erupted 15 billion years ago in an explosion called the ‘Big Bang’ and has been expanding and cooling ever since. Later there gradually emerged the conditions necessary for the formation of atoms, still later the condensation of galaxies and stars, and about 10 billion years later the formation of planets.
In our own solar system and on earth formed about 4. While there is little consensus among scientists about how the origin of this first microscopic life is to be explained, there is general agreement among them that the first organism dwelt on this planet about 3. Since it has been demonstrated that all living organisms on earth are genetically related, it is virtually certain that all living organisms have descended from this first organism. Converging evidence from many studies in the physical and biological sciences furnishes mounting support for some theory of evolution to account for the development and diversification of life on earth, while controversy continues over the pace and mechanisms of evolution.
Anticorrelated Rb-Sr and K-At age discordances, Leuchtenberg granite, NE Bavaria, Germany Received: 30 June /Accepted: 20 December Abstract The Leuchtenberg granite (Oberpfalz, NE In this study, the Rb-Sr and K-Ar dating methods are used to constrain the age distribution pattern with- in the Leuchtenberg granite, NE Bavaria.
Thanks mainly to the fact that they appear to be so constant, the decay rates of radioactive materials have become the primary mechanism for attempting to discover the age of rocks. A number of methods have been tried to calibrate the “radiometric clock”. But they have all required unprovable and apparently unwarranted assumptions.
Faure, in his textbook  refers to all of them as “assumed values” except for those obtained by the “isochron”, or similar linear method. The linear methods are several, and have in common the reduction of the data to a set which can yield a straight-line plot. Many exceedingly detailed descriptions of these methods are available.
Arndts and Overn alerted the creationist community to the fact that in spite of the mathematical rigor of the isochron, it also has unwarranted assumptions, and the data carefully gathered and processed to indicate immense ages can more appropriately be dismissed as indicating the recent mixing of two or more magmas. There is sound logic supporting the mineral isochron, but another fatal flaw.
Individual mineral crystals are not closed systems. Even over the few thousands of years available in the young-earth paradigm, they are insufficiently stable to give acceptable data to the geochronologists.
Methods of Dating the Age of Meteorites Meteorites are among the oldest objects we know about – formed about 4. But how do scientists know this? This article describes the principles and methods used to make that determination. There are well-known methods of finding the ages of some natural objects.
Although the unreliability of the Rb-Sr method for dating is readily demonstrated, 1,2 it is important that alternative models are developed to explain the observed patterns of strontium isotopes. The ratios of 88 Sr, 86 Sr, and 84 Sr, relative to each other, are commonly believed to be .
Single grain pyrite Rb—Sr dating of the Linglong gold deposit, eastern China This study employs the single grain pyrite Rb—Sr technique to date mineralization, using the exam The gold deposits in this area are interpreted to have a consistent spatial—temporal relationship with widespread Late Jurassic—Early Cretaceous magmatism in eastern China, likely related to lithospheric thinning around Ma.
Four pyrite samples from veins of different mineralization stages give an average isochron age of Analyses of one quartz and two sericite samples yield isochron ages between Ma and Ma. Hence, the successful attempt of the single grain Rb—Sr technique of pyrite, which occurs as a common mineral phase in orebodies and is genetically related to the mineralization, has great potential for precise geochronology of hydrothermal mineral deposits.
Compared to the K—Ar and 40Ar—39Ar results previously reported, these mica standards nevertheless show complex characteristics in the Rb—Sr isotopic system. Analysis on eight individual grains of GA biotite gives a Rb—Sr isochron age of Although evidence of the laser ablation 40Ar—39Ar analyses in many previous studies demonstrates that LP-6 biotite is considerably inhomogeneous in the K—Ar isotopic system, Rb—Sr isotopic analyses on ten individual biotite grains show achievement of Sr isotopic equilibrium during crystallization.
Rubidium–strontium dating – Wikipedia
The technique was tested using fluorite and calcite from three deposits ranging in age from Tertiary to Precambrian. In all cases the age determined here closely resembles that obtained by conventional K-Ar and Rb-Sr dating methods.
Chronological Methods 9 – Potassium-Argon Dating Potassium-Argon Dating Potassium-Argon dating is the only viable technique for dating very old archaeological materials. Geologists have used this method to date rocks as much as 4 billion years old. It is based on the fact that some of the radioactive isotope of Potassium, Potassium K ,decays to the gas Argon as Argon Ar By comparing the proportion of K to Ar in a sample of volcanic rock, and knowing the decay rate of K , the date that the rock formed can be determined.
How Does the Reaction Work? Potassium K is one of the most abundant elements in the Earth’s crust 2. One out of every 10, Potassium atoms is radioactive Potassium K These each have 19 protons and 21 neutrons in their nucleus. If one of these protons is hit by a beta particle, it can be converted into a neutron. With 18 protons and 22 neutrons, the atom has become Argon Ar , an inert gas.
For every K atoms that decay, 11 become Ar
Reliability of Geologic Dating
Acknowledgements Introduction his document discusses the way radiometric dating and stratigraphic principles are used to establish the conventional geological time scale. It is not about the theory behind radiometric dating methods, it is about their application, and it therefore assumes the reader has some familiarity with the technique already refer to “Other Sources” for more information. As an example of how they are used, radiometric dates from geologically simple, fossiliferous Cretaceous rocks in western North America are compared to the geological time scale.
The rubidium-strontium dating range rubidium-strontium dating method is a radiometric rubidium strontium rb sr dating example half life dating technique localhost:81 talked some to his friends, frequently saying, They have got me I am bound to localhost:81 respect to the general affairs of New Brunswick, it is very satisfactory to observe that the provincial revenue has increased to upwards.
At the time that Darwin’s On the Origin of Species was published, the earth was “scientifically” determined to be million years old. By , it was found to be 1. In , science firmly established that the earth was 3. Finally in , it was discovered that the earth is “really” 4. In these early studies the order of sedimentary rocks and structures were used to date geologic time periods and events in a relative way.
At first, the use of “key” diagnostic fossils was used to compare different areas of the geologic column.
Creation Science 10 of 10
Of course, both geologists and YECs agree that a ‘date’ of 34 billion years for this rock is completely ridiculous. Geochronologist Dalrymple , p. The diagram of the ‘diabase’ shows a terrible scatter and does NOT provide an isochron and an associated Rb-Sr date. Radiometric dating on related rocks, however, suggests that the ‘diabase’ is about 1.
LUMINESCENCE DATING TECHNIQUE – USU Luminescence Laboratory, Department of Geology, Utah State University Multimedia Luminescence Dating Technique (Text & Images). VERY EXTENSIVE. VERY EXTENSIVE. For more information see the Welcome to the GSA Pardee Symposium P4: SPEED DATING! or the Department of Geology.
Idealized and simplified diagram of the Grand Canyon There are a number of lava flows on the plateau that the canyon is cut into yellow in Figure 1, above. These lava flows are Cenozoic in age, and some of them spill into the canyon. The walls of the canyon are mostly cut into horizontal rock layers of Paleozoic age green in Figure 1, above. There is an angular unconformity at the bottom of the Paleozoic layers.
An angular unconformity is the result of tilting and eroding of the lower layers before the upper ones are deposited. These tilted and eroded layers are Precambrian in age blue in Figure 1, above. The geological relationships of the various formations are quite clear. The lava flows which spill into the canyon must be younger than the canyon. The canyon must be younger than the rock layers that it cuts into.
The sediments above the angular unconformity must be younger than the sediments below it.